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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?LQfa1RqB3+W8NHnHMCZx3ErUpIrn3do9TC3hiAH2GPTp7GsnroZR5crP/pvc?= =?us-ascii?Q?b28iZn6yLtUVuzlJXNRbq8oWlc2Nerd+zdQCDrmU1gdfTh7eET7C5zfh061z?= =?us-ascii?Q?xxjG0QZeKgHaiXEox2xyYe5l4iDyT4S+SvzNQzxh6si7F+LlyAWHGIB3IoR/?= =?us-ascii?Q?vbHK4gLiT0pbeE0UlOP4SfvH2szCgjhPzy/VvTQjcZsXQxLkW7d3Tu2+y6mu?= =?us-ascii?Q?LGJ6qBP/fi1akmtfyGIIuGxvFNOTGbl1vShxLx4CirWZqjtYgVHpM7lfgd/G?= =?us-ascii?Q?dmJNnAfni91E+CRSwzmtgB4lBkTcppRTGSAIeYkuxAfXM52Y+sio+UFzZ3Uw?= =?us-ascii?Q?knl27QnvjFg3r/mvJEMYp+8Pna1i6WhcUSAdR4MwNyHnuHoDsm9fW5v8CCa5?= =?us-ascii?Q?Tm9tKHvJQS9S0LtrqkJmSOS8OVb7KqNXWwas5WAY2y/WYc7RJJT4Z/yoYte7?= =?us-ascii?Q?bafVegd/jXl/kZpbqpQXPly3/t5qWNEyhHdJiV01XzqoPtAk+lX0z19795B8?= =?us-ascii?Q?3R7MUuOpIKFTHlDBEzI4k2tu+DPgebafJEDmF7NPHL3l59d+7t1r1GAwd5Su?= =?us-ascii?Q?3dZqhoypihchKxQhSnNhDxYj0T0bHNtO5ezvgH6RsdRXXxxaQweUTNUBiH4b?= =?us-ascii?Q?j8KTPLKokpIWgvNIsR2yMeWQJJp11SH48oqNAAD9tS16/zqL71iN7PAI3hkR?= =?us-ascii?Q?xL/Ssu1xRc6rHf6l8aK+XPCdnA2B5LJzyBVtDRHnl9fo7JSZe74oHXU8Pbg4?= =?us-ascii?Q?es9Ob1KRQhumrPafIgCfpOS4MOPR2U62Xetx5Bff+xEftSW4NsTrnnT+s1+K?= =?us-ascii?Q?UQ3HajHb2JoIcx0TtZ0MJv4OknH2u1t2fbrD/M/x4nlvG5OSuOArhna1OOtp?= =?us-ascii?Q?xkhG6RyISTJsOFIksvDMhwos9PRz/23RwI5yz+Qa5/a0TvBSkUBtNg72aQOU?= =?us-ascii?Q?/eESnLCTcY9dN8lOjv+gWMov+ciwPYoD0qnna4bfHtwLwiu5EjuYCOwZwuL3?= =?us-ascii?Q?XdsoZFDPekwzy8Wzm6BtJItr9VIHyQwOJGb5DPJcaYtHhaB16hBoMmEB7KIv?= =?us-ascii?Q?gN32rz9jTQ1gbO5lB3zSidasLtV5V7chE0I+tls0QD9+cNzig/fFr2f1QRil?= =?us-ascii?Q?BlSSMYTIqBQazANGfe0dh3l2WBuiB2sDE9qUT4q3nsvFu8dBM9dSOsPx1hN+?= =?us-ascii?Q?I1bN7YWeocB726YyA4Uo9fa8tw+jdWpXttNVPs2zByD6Q4cJ9e6Z7wiVJvzs?= =?us-ascii?Q?s3mMiGP0KgcgDj/AZx0zDUvFrBX8JyNVm6wPj4xtBm9aH9prcK8uZtxGBd6f?= =?us-ascii?Q?/Y77jFWArcbcOrenvxX+/uqsiIIJsRSb/2c1Uxezs3/JVBTLag/jNMl8uWvK?= =?us-ascii?Q?CBHHldvU0b/bxurQH5juo9gjuDI/msuVvL35K6kP6XfDURGsxEvn5vtZHy7A?= =?us-ascii?Q?20/ORIQj5+EhZe9tApEYIu88MkkbLm+S4Jn2yYr4+zYDbkWMEQoGvNJ2Y9CS?= =?us-ascii?Q?0bK1Mt0756KGdZ+uUVf58D1RngdrsKQEpZxgYAqOTeMHyOPYXSGh8vv4aRAw?= =?us-ascii?Q?+uZ4rcJrG+70XY7irvSYvS96azzSuQwlClnAql/z19fntAClJhn+Xgy9iok9?= =?us-ascii?Q?ABgol41NekDE/EUZjLeICB1ksXDCmKCsL7V7VZIaaC3tbenCSxLErViJRHaM?= =?us-ascii?Q?wlJ/E+YSwwM9q0SFUeQkNzqSgS4cMpU2Zb2/zL9IK1JPTeJ4?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: da8a0267-fbb2-4121-b950-08de869de339 X-MS-Exchange-CrossTenant-AuthSource: DS2PR12MB9615.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Mar 2026 16:29:41.6559 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: hDGRun3+foye9FXJ8/9s/lrvx969Iq1CRUp6ObVrgRi5NaPWrFUaaM3MGnCEKMFCSZuAhUTgUtXkzMqTrbgYDA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB8117 Hi Daniel, On Fri, Mar 20, 2026 at 11:57:02AM -0400, Daniel Jordan wrote: > Hi Andrea, > > On Wed, Mar 18, 2026 at 01:38:42AM +0100, Andrea Righi wrote: > > In the default built-in idle CPU selection policy, when @prev_cpu is > > busy and no fully idle core is available, try to place the task on its > > SMT sibling if that sibling is idle, before searching any other idle CPU > > in the same LLC. > > > > Migration to the sibling is cheap and keeps the task on the same core, > > preserving L1 cache and reducing wakeup latency. > > Seems reasonable. > > > On large SMT systems this appears to consistently boost throughput by > > roughly 2-3% on CPU-bound workloads (running a number of tasks equal to > > the number of SMT cores). > > What workloads out of curiosity? For the "server" side, I've used an internal benchmark suite, the workload that is showing the best results (3% speedup) is based on NVBLAS, but doing pure CPU activity. I've also tested this locally (AMD Ryzen 9 laptop), usual gaming benchmarks checking avg fps and tail latency. I noticed small improvements for this use-case as well (still in the 1-2% range, nothing impressive, but it looks consistent). Thanks, -Andrea